Oil palm is the largest national crop produced in Papua New Guinea. It is grown on over 80,000 ha of young volcanic soils in five Provinces, employs over 12,000 workers and uses >12,000 tonnes of fertiliser to offset nitrogen deficiency which is the most limiting factor to production. Oil palms strip out 160 - 200 kg N ha-1 yr-1 from the soil. Nitrogen fertilisers account for 60-70 % of all variable production costs but 40-60 % of applied fertiliser cannot be accounted for. Few studies have investigated the amounts of nitrogen lost via leaching, denitrification, volatilisation or as surface runoff in tropical soils and none have been done in Papua New Guinea. Oil palm soils typically have extremely high infiltrabilities (80-8,500 mm hr-1) and receive high annual rainfall which throughfall makes spatially non-uniform. The objective of this study was to assess and quantify nitrogen losses and suggest strategies that might assist in reducing them and their impact on the environment. The modest facilities available at the two research sites, West New Britain (Dami) and Oro (Sangara) Provinces, meant that no analytical work could be done on-site, so simple but appropriate methods were used to evaluate losses, with samples collected, preserved and sent off-shore for analysis. Large four-palm plots were used to evaluate runoff; a gas trap was used to collect evolved nitrous oxide, and lysimeters, suction cups and finally an in situ destructive soil sampling procedure were all used to assess leaching losses and the rate of nitrification of ammonium fertiliser. Results suggest that under the extreme total annual rainfall at Dami (3,500-4,000 mm) and to a lesser extent at Sangara (2,500-3,000 mm), leaching is the dominant loss pathway, with the rate of loss depending, to some extent, on the rate of nitrate formation and the retentivity of the soil for ammonium, but mainly on the rate at which drainage water is generated. A leaching model was developed that indicated that the average residence time of nitrogen fertiliser in the root zone (0-50 cm) varied from 21 days in February, at Dami, to 190 days in May, at Sangara.

For this dissertation I studied flow and transport in low gradient Florida streams. Chapter 2 is a statewide analysis of long-term variations in stream discharge. The results from Chapter 2 suggest that changes in mean annual stream discharge are controlled by the Atlantic Multi-Decadal Oscillation (AMO). During the warm phase, mean annual discharge decreases in central Florida and increases in north Florida. The opposite is true during the cool phase, with mean annual discharge increasing in central Florida and decreasing in north Florida. This pattern is observed for both components of stream discharge, base flow and runoff. The following two chapters are part of an analysis of particle transport in low gradient mangrove estuaries. Chapter 3 describes the use of a numerical model to simulate the hydrodynamics of a coastal reach of the Shark River, Florida Everglades and the development of a Lagrangian particle tracking model. The particle tracking model uses the output from the hydrodynamic model to simulate the movement of particles released within the model domain. In Chapter 4, the hydrodynamic and particle tracking models are used to estimate the historical particle residence time in the Shark River Slough Estuary (SRSE) and determine the key factors controlling particle residence time and fate in mangrove estuaries. The mean and median residence times in the model domain are 16 and 8 hours, respectively, and 60% of all particles exit the model domain downstream, towards the Gulf of Mexico. Particle residence time varies greatly depending on the particle release location and timing. The residence time is significantly lower for particles released in the middle of the channel and for particles released during the wet season, spring tides or during upstream flows. Additionally, there is a decreasing trend in mean particle residence time from 1997 through 2017, mirroring an increasing trend in mean annual water levels in the SRSE. The combined results of this dissertation show the impact that a variable climate can have on stream flow and particle transport.

Lack of water access is an issue of global importance. The WHO and UNICEF’s Joint Monitoring Program estimated that in 2015 71% of the world’s population used a safely managed drinking water source and 89% of the world’s population used an improved water source within a 30-minute round trip of home. Madagascar’s national statistics lags far behind these global statistics with 54% of the population using improved water sources, 31% using unimproved water sources, and 16% with no service at all. This research studied water access in Madagascar with self-supply Pitcher Pumps attached on hand-driven tubewells. The term self-supply in this context refers to privately owned and constructed water sources that are not financially subsidized by governments or non-governmental organizations. Self-supply is typically seen in the form of private wells in rural areas of developed countries like the United States or in developing countries in the form of shallow wells or rain water harvesting. Self-supply Pitcher Pumps are common along the coast in Madagascar in areas where the first aquifer is shallow and in sandy soil. They are ubiquitous at the site of this study, the port city of Tamatave. People in Madagascar have benefited from increased access to affordable water because of Pitcher Pumps for decades, however, there are health risks associated with consuming the water due to lead and microbial contamination of the water. This study sought to improve microbial water quality of Malagasy Pitcher Pumps by testing two different types of well head protection: 1) a partially buried short 100-mm diameter PVC pipe collar placed around the rising main, and 2) a 50-cm diameter, circular concrete apron. The study was a mixed design experiment that allowed for between subject comparisons of wells over the same time period and for within subject comparisons of the same well sites with different types of well head protection. Wells were selected for the study that had a high risk of localized pathways of contamination and low risks of aquifer contamination relative to other wells in the area. Membrane filtration was used for microbial water quality measurements and detected a wide spectrum of bacteria grown at 37◦ C. In this study, data from 690 water samples of 44 wells (with and without well protection added) over a 9 months period was analyzed. Weak but statistically significant (p ≤ 0.05) and marginally statistically significant (0.05 < p ≤ 0.10) correlations were found between bacteria concentrations and antecedent rainfall depth for wells with aprons but not for wells with a pipe collar or no protection. No statistically significant relationship was found between bacteria concentrations in wells and type of well head protection. The lack of reduction in bacteria concentrations with well head protection is likely due to the high density of on-site sanitation near the wells and the relatively shallow water table. Generally, study results indicate that there is a wide variation of bacteria concentrations both from the same well across many months and between wells that are near each other. The second observation is consistent with other studies of wells in the area. It appears as if the best solution for improving water quality from Malagasy Pitcher Pumps to a potable level is point-of-use treatment of the water.

Made available in DSpace on 2014-06-11T19:33:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-10-15Bitstream added on 2014-06-13T19:23:04Z : No. of bitstreams: 1 fontes_n_dr_rcla.pdf: 16005221 bytes, checksum: 77a209783372364874105e73404bf844 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A pesquisa discute critérios e instrumentos de planejamento de sistemas de espaços livres, considerando o conjunto de loteamentos no contexto de uma bacia hidrográfica. Questiona-se o padrão de reserva de “áreas verdes/sistemas de lazer” em função de critérios legais predominantemente quantitativos que vêm gerando fragmentação e inadequação sócioambiental do espaço urbano. Propõe-se uma metodologia para identificar áreas prioritárias para implantação de espaços livres em processos de parcelamento do solo, relacionando demandas sociais e ambientais. Os resultados finais contemplam uma base de dados na forma de “coleção de mapas” e “mapa síntese”, que pode subsidiar processos decisórios sobre a localização, distribuição e prioridades de usos que recaem sobre os espaços livres. Entre as variáveis contempladas, destacam-se leituras de setores urbanos carentes de espaços livres de caráter social-lazer e o mapeamento de áreas de concentração de escoamento superficial em concavidades de vertentes e fundos de vale, tratados como critérios qualitativos para a reserva de espaços livres. Diante da tendência à municipalização de processos de licenciamento e à redefinição de instrumentos de gestão e planejamento urbanos, espera-se favorecer a incorporação de novos critérios de reserva de espaços livres nessas instâncias, visando à valorização do espaço público e minimização de impactos ambientais nas cidades. / The research discusses planning tools for open spaces systems, taking into account urban land allotments in a basin setting. The green areas/leisure systems reserve pattern is questioned due to predominantly quantitative legal criteria which are causing fragmentation and inadequacy social and environmental of urban space. A methodology is proposed to identifying priority areas for open spaces in land allotments, taking into account the relationships between social and environmental demands. The final results comprehend a data base in form of “set of maps” and “synthesis map”, which permit to provide subsides to decisions processes of localization, distribution and priority of land uses in open spaces design. Amongst the considered variables, it is made remarkable readings of urban sectors with leisure open spaces needs and the mapping of runoff concentrated areas in concave slopes and valley beds, taken as qualitative criteria for open spaces reserves. Before the devolution trend of license processes and redefinition of managing and planning tools, it is expected to favor the adoption of new reserve criteria in those instances, aiming the enhancement of public spaces and minimization of environmental impacts in towns.

The main goal of this Diploma thesis is to describe an approach for modeling run-off triangles of nonlife insurance (calculation of IBNR reserve) based on state space models and apply the method to the selected run-off triangles. In difference from (Atherino a kol., 2010) the KFAS package in R software is used for modeling purposes in the numerical study at the end of the thesis. One provides a preview of various possibilities of data and model adjustment applied to the same run-off triangles in order to asses added value of these steps (logartihmic transformation of input data, interventions for outliers etc.). A special attention is devoted to lognormal modification of the basic state space model. An integral part of the numerical study in the thesis is a residual diagnostic of models and simulation approach to IBNR reserves. 1

Total organic carbon (TOC) is a critical parameter when investigating the health of aquatic ecosystems. This report details the findings of the study on fluctuations of TOC concentration in Fylleån catchment are between January 2001 and December 2023 (23-year period). The study provided valuable insights into the long-term trends in TOC concentrations and its association with changes in river water discharge and surface water temperatures. The study revealed significant spatial and temporal variations, with higher TOC levels in areas with intensive anthropogenic activities (downstream), and lower levels in forested regions (upstream). Temporally, TOC concentrations exhibit distinct seasonal patterns, peaking in late autumn and early winter due to increased organic runoff and decreasing in late spring and summer due to reduced precipitation and higher biological activity. Online datasets were downloaded to aid in the assessment of the presence of a seasonal trend in changes in riverine TOC concentration. The same dataset was used to calculate the correlation between seasonal TOC concentration and river discharge / surface water temperature. Upstream TOC concentration ranges were 5.5-13.97mg/l in winter, 5.97-11.07mg/l in spring, 8.63-20.37mg/l in summer and 7.07-20.73mg/l in autumn. Downstream TOC concentration ranges were 6.83-19.07mg/l in winter, 6.43-12.83mg/l in spring, 6.33-16.97mg/l in summer and 6.23-24.53mg/l in autumn. For all the three stations, standard deviation was lowest in spring (1.39, 1.58, &amp; 1.45) and highest in autumn (4.09, 3.06, &amp; 3.59) at Fylleån-fyllebro, Trönningeån-trönninge, and Lillån Ga Järnvägsbron respectively. There was a positive correlation between TOC concentrations and river discharge. Results for correlation between surface water temperature and seasonal TOC concentration were generally positive with only summers showing purely negative correlation. The study concluded that there are seasonal trends in TOC concentrations which are partly influenced by river discharge and surface water temperatures.

O presente trabalho desenvolve uma proposta para a avaliação da redução da vazão de pico do hidrograma do método racional, no contexto de bacias hidrográficas topograficamente planas. Entendem-se como planas aquelas localidades, cujas declividades médias características e/ou projetadas são inferiores a 0,5%. Pretende-se também neste trabalho apresentar metodologias e práticas de projeto de drenagem usualmente adotadas em regiões de características topográficas semelhantes. No desenvolvimento do estudo, foram discutidas as bases teóricas do Método Racional e outros métodos de avaliação hidrológica que procuram levar em conta o amortecimento da vazão durante o seu escoamento sobre o leito das vias. Apresentam-se também as bases científicas para a criação de um modelo hidrodinâmico a ser usado no estudo para a determinação do fator de redução da vazão de pico do hidrograma racional. A capacidade de escoamento em vias urbanas é então discutida, de forma a se justificar as relações criadas como conclusão do trabalho. O resultado final apresentado é o estabelecimento de uma relação entre a variação do pico da vazão do Método Racional, com a capacidade de armazenamento ou amortecimento de cheias existente nessas vias. Relações estas que, para fins práticos, significam tanto o incremento positivo no período de retorno do projeto, quanto a redução da vazão para efeito de dimensionamento de galerias. Tais resultados são demonstrados de forma prática por meio do estudo de caso no município de Praia Grande, o litoral sul paulista. / This work presents a proposal for estimating the reduction of the Peak Flow Rate determined by the Rational Method, considering flat basins as a main characteristic. It is considered flat, all of those basins in which the average slope on the streets are smaller than 0,5 %. It is also intentions of this work discuss methods and practices adopted to flat areas as urban drainage solutions and best management practices. Within this work, we also present all the theoretical basis of the Rational Method, among others, that try to fuse the street storm water storage capacity whit the conveyance capacity of a usual street. It is also presented theoretical basis of hydrodynamic models to be used as the main tool to determine de peak flow reduction factor of the Rational Method Hydrogram. Conveyance capacity of a usual street is discussed, street storm water conveyance capacity is also discussed in order to justify the relations proposed as a conclusion of this work. As a result of this work it is established a relationship between the Peak flow rate determined by the Rational Method and the street storm water storage capacity. In addition, this peak reduction can be used as a positive increment on the Recurrence Interval or as flow rate reduction when designing the sewerage system, which means implementation costs reduction. An application to the city of Praia Grande, located the Sao Paulo State, is presented and used as a case of study.

O presente trabalho desenvolve uma proposta para a avaliação da redução da vazão de pico do hidrograma do método racional, no contexto de bacias hidrográficas topograficamente planas. Entendem-se como planas aquelas localidades, cujas declividades médias características e/ou projetadas são inferiores a 0,5%. Pretende-se também neste trabalho apresentar metodologias e práticas de projeto de drenagem usualmente adotadas em regiões de características topográficas semelhantes. No desenvolvimento do estudo, foram discutidas as bases teóricas do Método Racional e outros métodos de avaliação hidrológica que procuram levar em conta o amortecimento da vazão durante o seu escoamento sobre o leito das vias. Apresentam-se também as bases científicas para a criação de um modelo hidrodinâmico a ser usado no estudo para a determinação do fator de redução da vazão de pico do hidrograma racional. A capacidade de escoamento em vias urbanas é então discutida, de forma a se justificar as relações criadas como conclusão do trabalho. O resultado final apresentado é o estabelecimento de uma relação entre a variação do pico da vazão do Método Racional, com a capacidade de armazenamento ou amortecimento de cheias existente nessas vias. Relações estas que, para fins práticos, significam tanto o incremento positivo no período de retorno do projeto, quanto a redução da vazão para efeito de dimensionamento de galerias. Tais resultados são demonstrados de forma prática por meio do estudo de caso no município de Praia Grande, o litoral sul paulista. / This work presents a proposal for estimating the reduction of the Peak Flow Rate determined by the Rational Method, considering flat basins as a main characteristic. It is considered flat, all of those basins in which the average slope on the streets are smaller than 0,5 %. It is also intentions of this work discuss methods and practices adopted to flat areas as urban drainage solutions and best management practices. Within this work, we also present all the theoretical basis of the Rational Method, among others, that try to fuse the street storm water storage capacity whit the conveyance capacity of a usual street. It is also presented theoretical basis of hydrodynamic models to be used as the main tool to determine de peak flow reduction factor of the Rational Method Hydrogram. Conveyance capacity of a usual street is discussed, street storm water conveyance capacity is also discussed in order to justify the relations proposed as a conclusion of this work. As a result of this work it is established a relationship between the Peak flow rate determined by the Rational Method and the street storm water storage capacity. In addition, this peak reduction can be used as a positive increment on the Recurrence Interval or as flow rate reduction when designing the sewerage system, which means implementation costs reduction. An application to the city of Praia Grande, located the Sao Paulo State, is presented and used as a case of study.

Big-box Urban Mixed-use Developments (BUMDs) are mixed-use developments with a consistent typology that incorporate big-box retailers in a central role. They are also becoming popular in the Atlanta region. While BUMDs serve an important economic role, they also cause issues with stormwater. This study explores integrating a on-site approach to stormwater management into the design of BUMDs. These new designs not only significantly lower the amount of stormwater run-off, but also have potential for better, more attractive, developments.

Urbanization causes various environmental issues including water pollution, air pollution, and solid waste. Urbanization of watersheds has a profound influence on the quality of stormwater runoff. The quality of stormwater runoff is highly associated with land use. This study analyzed the exceedance frequency of stormwater quality in five watersheds of Denton over eleven years and also analyzed the relationship between stormwater quality and land use/cover of each watershed. The results showed that the most of the water quality parameters that were examined in the Lower Pecan watershed exceeded their threshold most frequently. The higher frequency of exceedance in this watershed can be attributed to the wastewater treatment plant and landfill site. Total suspended solids and turbidity were frequently exceeded in Hickory and Clear Creek watersheds. Conductivity was found to have highest percentage of exceedance in Upper Pecan and Cooper watersheds. Thus, rural watersheds were related with higher exceedance of TSS and turbidity whereas urban watersheds were related with higher exceedance of conductivity.